1. Technical Field
The present invention relates to a composite material structure forming method.
2. Description of the Related Art
A structure made of a composite material such as a fiber-reinforced plastic (FRP) is widely used as a high-strength lightweight structure, for example, in an aircraft and a windmill. Such a composite material structure is generally formed by heating and pressurizing a prepreg in an autoclave.
When a composite material structure is formed by heating and pressurizing a prepreg in an autoclave, a jig is provided on one surface of the composite material structure to be formed, and thus a variation occurs in shape and dimension of a side on which the jig is not provided. In particular, the dimensional accuracy of an outer periphery of a hollow object such as an aircraft wing affects the performance. Thus, the shape accuracy of a bonding surface needs to be increased to have a predetermined outer shape and dimension in a bonding assembly step.
In view of this, in order to make the outer shape and dimension of the hollow object into a predetermined shape and dimension, there is used a method of forming a composite material structure using a core material such as a pressurizable expandable pressure bag, a closed mold, and a thermoplastic foam material to press it outward from the interior of the hollow body (for example, see Japanese Patent Publication No. 1474023 and Japanese Patent Publication No. 3631493).